Butterscotch Ice Cream Squares

My friend Dana's recipes are always worth keeping.

2 c. flour
½ c. oats
½ c. brown sugar
1 c. butter
1 c. chopped nuts
2 qt. vanilla ice cream
1 jar (12-oz.) butterscotch or caramel topping
        Combine flour, oats and sugar. Cut in butter until it resembles coarse crumbs. Add nuts and pat into 9x13 pan. Bake at 400° for about 15 minutes or until lightly browned. Stir while warm to crumble. Cool. Spread half in 9x13 pan. Drizzle with ½ the topping. Stir ice cream to soften and spoon it carefully into the pan. Drizzle with remaining topping and sprinkle with remaining crumbs. Freeze. Cut into squares.